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Zooxanthellae purpose

Microscopic view of zooxanthellae

Tiny cells called zooxanthellae live within most types of coral polyps. They help the coral survive by providing it with food resulting from photosynthesis. In turn, the coral polyps provide the zooxanthellae with a protected environment and the nutrients they need to carry out photosynthesis. Photo credit: Giada Tortorelli/HIMB